Currently, Liquid Crystal Display (LCD) has become a major trend in display field. An array substrate of the LCD comprises a pixel region and a peripheral wiring region surrounding the pixel region, the peripheral wiring region is configured for connecting with a drive IC, testing and preventing static electricity, etc.; and the peripheral wiring region is provided with a variety of metal wirings. Due to the limitation of the arrangement manner and the arrangement space of the metal wirings, via holes are generally employed to connect the metal wirings provided in different layers; however, a corrosion phenomenon often occurs at the locations of the via holes.
For example, a gate line lead in the peripheral wiring region and a gate electrode in the pixel region are provided in the same layer and are formed simultaneously. The gate line lead in the peripheral wiring region is often buried under the surface of the array substrate and the gate line lead needs to be connected with the drive IC; to this end, a metal oxide conductive electrode with relatively strong corrosion resistance is provided on the surface of the array substrate and a via hole is provided in an insulating layer below the metal oxide conductive electrode so that the metal oxide conductive electrode is electrically connected with the gate line lead below the via hole and the gate line lead is connected with the drive IC through the via hole and the metal oxide conductive electrode.
Although the corrosion resistance of the metal oxide conductive electrode exposed in the air is relatively strong, yet water vapor in the air will inevitably permeate into the metal oxide conductive electrode and arrive at the gate line lead through the via hole to cause corrosion to the metal gate line lead. Thus, a yield of the array substrate is reduced.